Daz Error: empty renders when using Iray and GPU for some scenes.

[lawfullame]

Sometimes it happens to me that when I render a scene, the rendering stops and the result is an empty canvas. Sometimes it helps to restart Daz and start rendering again. But sometimes it does not help and it happens over and over again. This does not happen with CPU rendering.

This is not the same problem as when the GPU is low on memory. In case of low GPU memory, DaZ automatically falls into the CPU rendering, but the rendering is not interrupted.

Do you have experience what causes this problem? Does this mean that some object in the scene is corrupted?

 

[Porcus Dev]

If there is an object blocking the view, it will happen to you rendering with both GPU and CPU; if it works well with CPU, that shouldn't be the problem.

Have you tried updating the GPU drivers? Or, if you have the latest, try a previous version (I know that some versions had problems)?

 

[9thCrux]

Some other things you can do is to check if the camera focal distance and focal stop are set up right, also check if the camera is not clipping with some geometry.

I have get a similar errors when trying to render images using different aspect ratios, or pixel size (Global), review your dimension preset.

Also check your system temperature, maybe your computer is overheating.

 

[lawfullame]

If there is an object blocking the view, it will happen to you rendering with both GPU and CPU; if it works well with CPU, that shouldn't be the problem.

Have you tried updating the GPU drivers? Or, if you have the latest, try a previous version (I know that some versions had problems)?

Yes, this is always the case where the same scene works for CPU rendering, and problems only occur with GPU rendering.
The drivers are up to date. But I have a pretty old GPU, GeForce 960m with 4GB RAM.

But it works well in many scenes. I only have problems with some scenes.

 

[Winterfire]

I believe that some scenes are simply too complex for you to render, I have a similar experience...
With a GeForce 610M, I can render only naked women (or partially clothed), up until a certain resolution.
Anything more than that will cause a blank render.

 

[lawfullame]

Strangely, in some cases I have problems with scenes that require relatively little memory, and rendering some of the more complicated scenes works smoothly.
Usually something like this appears in the log:

2019-08-19 16:49:45.703 WARNING: ..\..\..\..\..\src\pluginsource\DzIrayRender\dzneuraymgr.cpp(302): Iray ERROR - module:category(POST:RENDER): 1.0 POST rend error: A CUDA error occurred: unknown error
2019-08-19 16:49:45.703 WARNING: ..\..\..\..\..\src\pluginsource\DzIrayRender\dzneuraymgr.cpp(302): Iray ERROR - module:category(POST:RENDER): 1.0 POST rend error: Exception during postprocessing: unknown error
2019-08-19 16:49:45.703 WARNING: ..\..\..\..\..\src\pluginsource\DzIrayRender\dzneuraymgr.cpp(302): Iray ERROR - module:category(IRAY:RENDER): 1.0 IRAY rend error: Internal error in postprocessing pipeline.
2019-08-19 16:49:45.703 Iray Render error: Internal rendering error.
2019-08-19 16:49:45.891 Iray VERBOSE - module:category(IRAY:RENDER): 1.0 IRAY rend progr: Transaction closed, stopping renderer.

 

[Winterfire]

Could it be the resolution? In my case it is pretty straight forward so I always assumed it is my GPU which is pretty old anyways.

 

[lawfullame]

I almost always use the same resolution 1920 x 1080.
Maybe something related to the lights? I often use ghost lights.
Or maybe denoiser? But I never let a denoiser run from the beginning, I always let it activate a few iterations before the end, if I use it at all.

 

[Winterfire]

In game engines lights (each light) double the draw calls, I do not see why it would be any different in DAZ3D, so although I am quite ignorant about DAZ3D, I can at least assume that that may be the cause.
I cannot confirm for sure tho.

 

[lawfullame]

It seems that the problem was only in DaZ 4.11, in 4.12 beta I have not encountered it yet.

 

[Winterfire]

Oh really? That is interesting, I may give it a try then. Thanks.

 

[lawfullame]

I'll let you know if I run into the problem later in 4.12.
By the way, when I rendered a pretty demanding scene in DaZ 4.12 that barely fit into GPU memory, rendering was not much faster than CPU rendering. But even relatively slow GPU rendering is better for me than CPU rendering because sometimes CPU rendering can basically freeze the laptop. In the case of GPU rendering, the laptop is usable for other work during rendering.

For less demanding scenes, the difference between GPU and CPU rendering is greater on my laptop.